In response to an increased public concern about negative health effects of trans-fatty acids the food industry faces the task of replacing hydrogenated fats in product formulations with trans-free alternative fats or with fats having a low trans-fat content.
The confectionary and baking industries are particularly concerned, because for their highly demanding fat applications it has proved difficult to find non-hydrogenated fats that are both economical and functional alternatives to hardened fats.
The problem of providing products with a low percentage of trans fatty acids (less than 10%, preferably less than 5%, most preferably less than 2%) is even bigger in the field of chocolate applications.
The mixing between “real” chocolate and vegetable fats/oils is known. Yet, when vegetable fats and/or oils other than Cocoa Butter Equivalents (CBE), or other than Cocoa Butter Replacers (CBR) based on hydrogenated fats (see below), are mixed with cocoa butter, a high-quality, stable, homogeneous and well crystallized chocolate product with the desired texture is not easy to obtain.
Cocoa butter (CB) has some particular properties. CB is a stiff solid at room temperature, but melts smoothly in the mouth. It has a narrow melting range and shows specific shrinking properties on cooling to solidify.
CB is a polymorphic product and the fats therein can crystallize in six different forms (polymorphous crystallization). Making good chocolate is about forming the most of the type V crystals (Beta form). Tempering is therefore an important step in the production of chocolate and chocolate products such as fillings.
A CBE is a fat which does not alter physical properties of CB in any mixture with CB. This type of fat therefore must have a composition very similar to that of CB (see e.g. WO 03/037095).
A CBE composition is a fat composition of which the solid fat content measured at 30° C. with IUPAC method 2.150 a, the fat composition not being subjected to a thermal treatment, differs at least 8% absolute from the solid fat content measured at the same temperature with IUPAC method 2.150b, the fat composition this time being subjected to a thermal treatment program described in that method (see WO 03/053152).
Another group of vegetable fats and/or oils (fats/oils) that are quite easy to blend with real chocolate is formed by the Cocoa Butter Replacers (CBR) based on hydrogenated fats or on the non-tempering and non-lauric fats (see WO 03/053152 and WO 03/037095).
Traditional type CBR fats are produced from standard raw materials for oil and fats such as palm oil, soybean oil and rapeseed oil. These CBR products crystallize directly into the stable crystal form when cooled. This means that in contrast to cocoa butter and CBE, no tempering is needed. In addition, CBR—and in particular the traditional type—are fast setting fats.
This type of vegetable oils, however, are hydrogenated under selective conditions (a process referred to as “partial hydrogenation”) so that the naturally occurring cis unsaturated fatty acids are largely converted into trans unsaturated fatty acids with very little formation of saturated fatty acids. A hardened fat fraction of this type is compatible with up to 25% of cocoa butter (Biscuits, cookies and Crackers, Vol. 3; 2.6.2 Cocoa butter substitutes—Nonlauric cocoabutter replacers, Almond N., Gordon M. H., Reardon P, Wade P (eds), Elsevier Applied Science, 1991, London).
There are several reports that indicate an incompatibility of different types of non-hydrogenated fats and oils when used in combination with more than 10% (w/w) cocoa butter (CB) in standard methods and applications. This incompatibility would be caused amongst others by a different crystallization rate founded in different fatty acids compositions and triglyceride structures of the fats.
Danisco has produced specialty emulsifier blends to secure fast fat crystallization and to help food makers use trans-free fats without loosing functionality.
Another approach has existed in the use of new specialty fats like some trans-free palm oil fractions that have been developed to have a crystallization rate as close as possible to that of hydrogenated fats.
However, despite of the equal crystallization rates of hydrogenated fats and of these trans-free alternatives as measured on the pure fat, there are still differences between the crystallization behavior of both, which appears to require the adjustment of existing process technologies in some applications.
In hydrogenated fats the fast crystallizing trans-fatty acids are present in the majority of triglycerides which facilitates an even and continuous crystallization process of the bulk of a hydrogenated fat during cooling.
In the non-hydrogenated trans-free fat blends, a rapid solidification onset followed by a slower completion of crystallization of the remaining fat phase is observed.
Also WO 03/037095 discloses particular trans-free fat fractions tailored to be compatible with fats that require tempering like cocoa butter (CB). The non-LTT specialty fats disclosed herein have a crystallization rate comparable to that of trans-hydrogenated fats.
EP 1 491 097 discloses a method for producing particular hydrogenated low-trans non-tempering fats with a steep SFC profile for confectionary applications. The trans-fatty acids (TFA) content of the fats actually used in said documents is at least 7 wt. %.
There is thus a demand for novel and improved processes that allow the production of trans-free chocolate products (e.g. fillings), in particular for chocolate products (e.g. fillings) with a TFA content lower than 2% or even lower than 1%, without the need to use specialty products.
Because chocolate and chocolate products such as fillings are used in a vast number of foods, any change in the cost of making such products has a huge impact on the industry.